1. The Field of the Invention
The present invention relates to radio frequency links to computing devices. More particularly, the present invention is related to a wireless attachment of electronic peripheral devices to one or more portable computer systems across an RF link.
2. Present State of the Art
Portable or laptop computers can be interfaced to a variety of peripheral devices such as printers, modems, storage devices, and local area networks. To interface the computer to these peripheral devices, a serial or parallel port is typically used. Other ports such as a Universal Serial Bust (USB) port, can also be used.
As computer housings have been continued to be down-sized, internal spacial restrictions have required the establishment of standards for the internal accessories of the computer, particularly with respect to interfacing peripheral devices to the computer housing. One set of standards applicable to memory cards for computers and the attachment of peripheral devices thereto has been developed by the Personal Computer Memory Card Industry Association (PCMCIA).
The PCMCIA standard determines that the spacial standard for all memory cards used in down-sized computers should be restricted to a rectangular space approximately 55 mm in width and 84 mm in length. PCMCIA has set forth standards for three different sizes of cards known respectively as Type I (3.3 mm thick), Type II (5.0 mm thick) and Type III (10.5 mm thick) PC cards. Connectors and guide rails are standardized in all types. These standards, current and future, are referred herein as xe2x80x9cthin-architecturexe2x80x9d standards. A personal computer card (PC Card) having a thin architectural standard, such as a PCMCIA card, can be used to interface a peripheral to a portable computer.
An electronic device which can be installed on the PCMCIA card is a wireless modem. A wireless modem device enables a portable computer system to communicate with electronic peripheral devices and other computer systems without requiring physical access to land line communication ports. Portable computers with wireless modems can be used in wireless Local Area Networks (LANs). Also, mobile terminals, such as Personal Digital Assistants (PDAs), specialized handheld terminals, and barcode scanners, can be in electronic communication with wireless LANs.
Wireless connections to peripheral devices can be used to significantly increase the profitability of business operations. Mobile data applications can cut operational costs by increasing the productivity of essential personnel. Wireless computing apparatus can also be used to increase revenues by bringing products, services, and transaction points, closer to users. Mobile data networks can be used to increase productivity and quality by providing convenient access to information that results in improved promptness, accuracy, and productivity of users having access to mobile computing devices that are connected wirelessly to a LAN. The realization of administration productivity eliminate redundant paperwork recording services.
The wireless modem typically consists of both a radio portion and a baseband portion. The transmitter in the radio portion generates RF signals using a baseband signal to modulate the carrier signal. The receiver in the radio portion produces a baseband signal from the received RF signals by demodulating the RF signals. An antenna is used for transmitting and receiving the RF communication signals. The baseband portion provides a baseband signal to the transmitter and accepts baseband signals from the receiver.
Portable computer systems such as laptop or notebook computers can be equipped with a wireless modem. A wireless modem can be installed in a PC adapter card or in a PCMCIA adapter slot. One of the constraints of mechanical package designs for PC peripheral card assemblies is that the design has a form factor meeting the requirements for products specified under the PCMCIA standard. PC cards have been designed to contain a variety of electronic devices, such as wireless modems, within the standards of form factor constraints.
The PCMCIA recognizes that rapid advances in the miniaturization of components are allowing developers to place more functionality on a single PC Card. Providing multiple functions on a single PC Card, such as modem and LAN functionality, effectively doubles the amount of functionality that each PC Card slot provides in a so-called xe2x80x9cCombo-Cardxe2x80x9d. Although PCMCIA has issued standards for devices such as Multiple Function PC (MFPC) Cards that handle PC Cards delivering multiple I/O functionality to a host platform in a generic manner, problems still remain. With this increase in the amount of functionality in the Combo-Card or MFPC Card, xe2x80x98real estatexe2x80x99 or space constraints of the increased functional integration in a limited form factor present problems. Additionally, complexity and costs of manufacturing the Combo-Card or MFPC Card are problematic.
A problem with thin architecture PC Card technology is that there is a limited number of peripheral devices that can be directly connected to a portable computer. Typically, a maximum of eight devices can be connected to a laptop computer via a thin architecture PC Card. As set forth above, the PCMCIA standard limits the amount of room that can be used for connecting peripheral devices to a portable computer. These form factor limitations pose a significant problem. Additionally, a large amount of circuitry within the PCMCIA standard form factor can cause a significant build up in temperature.
While a peripheral device can be attached or interfaced with a PCMCIA card by a cable, it is also known to use a wireless radio frequency link in a PC Card to connect a peripheral device to the portable computer by the thin architecture PC Card. For the most part, only one peripheral device can be connected to the notebook computer wirelessly using a thin architecture PC Card.
It would be an advancement in the art to provide a computing apparatus, such as a portable personal computer, with a wireless modem, such as a wireless modem in a PC Card or in a PCMCIA card, where the wireless modem is in electrical communication with one or more peripheral devices by an RF link.
It would also be an advancement in the art to provide a larger number than eight peripheral devices in wireless communication with a PCMCIA card in a portable computer or other computing apparatus, while minimizing thermal buildup and without exceeding the form factor limitations of the PCMCIA standard.
It is an object of the invention to wirelessly connect a portable computing device to a peripheral having a bandwidth that is used in conjunction with spread spectrum technology. As used herein a spread spectrum signal is a signal at frequencies between about 2.2 GHz to about 2.6 GHz in any system that occupies more bandwidth than the minimum required for data signal transfer.
It is a further object of the invention to use a thin architecture PC Card in a portable computing device, the PC Card having a wireless transreceiver operating a spread spectrum schema to interface the same with peripheral devices connected to a docking station also having a transreceiver operating at a similar frequencies, where the docking station is interfaced with the peripheral devices.
It is a further object of the present invention to provide a system having a plurality of computing apparatus each of which is interfaced with a transreceiver, each transreceiver being in a wireless communication system using a spread spectrum technology with a docking station, the docking station having a transreceiver and a digital signal processor or microprocessor in electrical communication with a plurality of peripheral interfaces, each peripheral interface being in communication with a peripheral device.
It is yet a further object of the present invention to provide a computing apparatus having a RF communication circuit capable of interfacing with a plurality of peripheral devices while minimizing the amount of hardware required to interface with the peripheral devices.
It is a further object of the present invention to provide a portable computer having a PCMCIA card interface that is in a wireless communication system via an RF link to a plurality of peripheral devices.
It is a still further object of the present invention to identify peripheral devices and their respective capability via an RF link using spread spectrum technology to interface with a portable computer having a thin architecture PC Card interface thereto.
To achieve the foregoing objects, and in accordance with the invention as embodied and broadly described herein, a computing system has a peripheral device for executing an input and or output (I/O) message and a computing device having a transreceiver. The transreceiver transmits a host spread spectrum signal that identifies the pattern of the host spread spectrum signal and the address of the peripheral device that is to execute an I/O message in the host spread spectrum signal. The transreceiver also receives a peripheral spread spectrum signal that identifies the pattern of peripheral spread spectrum signal and the address of the computing device to which an I/O message in the peripheral spread spectrum signal is directed.
Another transreceiver, different than the transreceiver of the computing device, is interfaced to the peripheral device. This transreceiver transmits a peripheral spread spectrum signal from the peripheral device that identifies the pattern of the peripheral spread spectrum signal and the address of the computing device to which an I/O message in the peripheral spread spectrum signal is directed. Also, this transreceiver receives a host spread spectrum signal that identifies the pattern of the spread spectrum signal and the address of the peripheral device that is to execute an I/O message in the host spread spectrum signal.
In another embodiment, the inventive computing environment has a plurality of portable computers each having a PCMCIA card that has an RF transreceiver. Each portable computer uses its RF transreceiver in a spread spectrum wireless link to give output to and receive input from a plurality of peripheral devices. Each RF transreceiver sends and receives spread spectrum signals, where each sent spread spectrum signal identifies and makes a demand upon a particular one peripheral device. The spread spectrum signals from the transreceiver on each PCMCIA card are received by a tranreceiver on a docking station that is interfaced to the plurality of peripheral devices. The docking station xe2x80x98de-spreadsxe2x80x99 the spectrum signals and then directs the same to the particular interfaced peripheral device identified in the signal. Similarly, each interfaced peripheral device sends a signal to the docking station that identifies a particular portable computer for spreading and transmission via the transreceiver and its docking station. A particular portable computer identified in the signal from the docking station then receives input from the sending peripheral device after the xe2x80x98de-spreadingxe2x80x99 of the signal. As such, each portable computer stretches its PCMCIA interface to respective peripheral devices across a spread spectrum communications link in the sending and receiving of data.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims.